Method of preparing acryloxy-functional organosilicon compounds

Abstract

A method of preparing an acryloxy-functional organosilicon compound is provided. The method comprises reacting (A) an initial organosilicon compound and (B) an acrylate compound in the presence of (C) a catalyst. The initial organosilicon compound (A) has one alcohol functional group (i.e., is monohydroxyl functional). The catalyst (C) has the formula M[RC(O)CHC(O)R] 4 , where M is a group IV transition metal and each R is an independently selected substituted or unsubstituted hydrocarbyl group. An acryloxy-functional organosilicon compound prepared by the method is also provided. The acryloxy-functional organosilicon compound is prepared in increased purity, without relying on toxic catalysts.

The invention claimed is: 
     
       1. A method of preparing an acryloxy-functional organosilicon compound, said method comprising:
 reacting (A) an initial organosilicon compound having one alcohol group and (B) an acrylate compound in the presence of (C) a catalyst having the formula M[RC(O)CHC(O)R] 4 , where M is a group IV transition metal and each R is an independently selected substituted or unsubstituted hydrocarbyl group, thereby preparing the acryloxy-functional organosilicon compound; 
 wherein the initial organosilicon compound (A) is mono-hydroxy functional and comprises a branched siloxy group. 
 
     
     
       2. The method of  claim 1 , wherein in the catalyst (C): (i) M is Zr or Hf; (ii) each R is independently CH 3  or CH 2 CH 3 ; or (iii) both (i) and (ii). 
     
     
       3. The method of  claim 1 , wherein the initial organosilicon compound (A) has the following formula:
   [R 3   3 SiO 1/2 ] a [R 3   2 SiO 2/2 ] b [R 3 SiO 3/2 ] c [SiO 4/2 ] d , 
 
       where each R 3  is independently selected from substituted or unsubstituted hydrocarbyl groups and linear or branched siloxy groups, with the proviso that one R 3  comprises an alcohol group; and subscripts a, b, c, and d are each mole fractions such that a+b+c+d=1, with the proviso that a+b+c>0. 
     
     
       4. The method of  claim 1 , wherein: (i) the initial organosilicon compound (A) and the acrylate compound (B) are reacted in a molar ratio of from 0.1 to 20 (A):(B); (ii) the initial organosilicon compound (A) and the acrylate compound (B) are reacted at a temperature of from 25 to 180° C., optionally from 80 to 120° C.; (iii) the catalyst (C) is utilized in the reaction in an amount of from 0.05 to 10 mole % based on the combined amounts of components (A), (B), and (C); or (iv) any combination of (i) to (iii). 
     
     
       5. The method of  claim 1 , wherein the acrylate compound (B) has the following formula: 
       
         
           
           
               
               
           
         
       
       where R 1  is selected from substituted or unsubstituted hydrocarbyl groups and H; and R 2  is a substituted or unsubstituted hydrocarbyl group having from 1 to 4 carbon atoms. 
     
     
       6. The method of  claim 5 , wherein in the acrylate compound (B): (i) R 1  is H or CH 3 ; (ii) R 2  is CH 3 , CH 2 CH 3 , or CH 2 (CH 2 ) 2 CH 3 ; or (iii) both (i) and (ii). 
     
     
       7. The method of  claim 1 , wherein the initial organosilicon compound (A) has the following formula: 
       
         
           
           
               
               
           
         
       
       where X is a divalent linking group; and each R 3  is independently selected from substituted or unsubstituted hydrocarbyl groups and linear or branched siloxy groups. 
     
     
       8. The method of  claim 7 , wherein the divalent linking group X comprises: (i) a substituted or unsubstituted hydrocarbon group having from 1 to 16 carbon atoms; (ii) a hydrocarbon moiety having the formula —(CH 2 ) n —, where subscript n is from 1 to 16; (iii) an ether moiety; (iv) an alkylamino moiety; or (v) any combination of (i) to (iv). 
     
     
       9. The method of  claim 1 , wherein the initial organosilicon compound (A) and the acrylate compound (B) are reacted in the presence of (D) a polymerization inhibitor. 
     
     
       10. The method of  claim 9 , wherein the polymerization inhibitor (D) comprises: (i) a radical scavenger; (ii) an antioxidant; (iii) a light stabilizer; (iv) a UV-absorber; or (v) any combination of (i) to (iv). 
     
     
       11. The method of  claim 1 , wherein reacting the initial organosilicon compound (A) and the acrylate compound (B) forms a reaction product comprising the acryloxy-functional organosilicon compound; and wherein the method further comprises isolating the acryloxy-functional organosilicon compound from the reaction product. 
     
     
       12. The method of  claim 11 , wherein the reaction product further comprises an organic alcohol formed by reacting the initial organosilicon compound (A) and the acrylate compound (B); and wherein the method further comprises removing the organic alcohol from the reaction product. 
     
     
       13. An acryloxy-functional organosilicon compound prepared in accordance with the method of  claim 1 . 
     
     
       14. The acryloxy-functional organosilicon compound of  claim 13 , having the following formula: 
       
         
           
           
               
               
           
         
       
       wherein Y comprises an organosilicon moiety; X is a divalent linking group; and R 1  is independently selected from substituted or unsubstituted hydrocarbyl groups and H. 
     
     
       15. The acryloxy-functional organosilicon compound of  claim 14 , wherein the organosilicon moiety Y is a silane moiety having the formula (R 3 ) 3 Si—, where each R 3  is independently selected from substituted or unsubstituted hydrocarbyl groups and linear or branched siloxy groups. 
     
     
       16. The acryloxy-functional organosilicon compound of  claim 14 , wherein the organosilicon moiety Y is an organopolysiloxane having the formula:
   [R 3   3 SiO 1/2 ] a [R 3   2 SiO 2/2 ] b [R 3 SiO 3/2 ] c [SiO 4/2 ] d , 
 
       where each R 3  is independently selected from substituted or unsubstituted hydrocarbyl groups and linear or branched siloxy groups, with the proviso that one R 3  is a silicon-bonded divalent linking group; and subscripts a, b, c, and d are each mole fractions such that a+b+c+d=1, with the proviso that a+b+c>0. 
     
     
       17. The acryloxy-functional organosilicon compound of  claim 14 , wherein: (i) divalent linking group X is a substituted or unsubstituted hydrocarbon group having from 1 to 16 carbon atoms; (ii) R 1  is H or CH 3 ; or (iii) both (i) and (ii). 
     
     
       18. The acryloxy-functional organosilicon compound of  claim 14 , wherein the divalent linking group X comprises: (i) a substituted or unsubstituted hydrocarbon group having from 1 to 16 carbon atoms; (ii) a hydrocarbon moiety having the formula —(CH 2 ) n —, where subscript n is from 1 to 16; (iii) an ether moiety; (iv) an alkylamino moiety; or (v) any combination of (i) to (iv).